1. Field of the Invention
The present invention relates to an apparatus for automatically determining color/monochrome of a document image, a method of controlling the apparatus, a program of the apparatus and an image processing apparatus provided with the apparatus.
2. Description of the Related Art
There conventionally exists a Multifunction Peripheral (MET) reading a document with an image reading apparatus (scanner) and provided with an auto color selection (ACS) function of automatically determining whether the obtained document image is a colored document or a monochrome document.
Such MFP is used for an output service of an accounting system in a variety of scenes such as convenience stores or libraries. In such output service, print output is made according to the determination result by the auto color selection function and the accounting is performed corresponding to the print output. For example, in a case where it is determined that the document is a colored document, the print output is made in color to charge 40 yen per sheet and in a case where the document is a monochrome document, the print output is made in monochrome to charge 10 yen per sheet.
However, it is difficult to always perform the automatic determination with high accuracy on whether the document is the monochrome document or the colored document in regard to all products. This is because even if the MFP is provided with the same model number and the same specification, each incorporated scanner has an individual difference and the reading characteristic thereof varies more or less.
That is, a scanner of some MFP can read an image very accurately, but on the other hand, a scanner of the other MFP has a reading performance more than a predetermined level but can not read an image so much accurately.
For preventing variations in performance of the ACS function due to the individual difference of such scanner from being generated between products, an image processing parameter in the ACS function has been standardized so far. That is, even in the MFP equipped with a scanner which can read an image with extremely high accuracy, by performing the parameter setting for restricting the performance, variations in performance between products based upon the individual difference of the scanner are absorbed. In other words, there exist not a few MFP which can not achieve the performance sufficiently although they can effect high ACS performance.